A laminated glass obtained by laminating a pair of glass substrates through a heat reflective film sandwiched between a pair of adhesive layers has conventionally been known as a laminated glass used in a wind shield of vehicles and the like. Such a laminated glass is manufactured by, for example, overlaying a glass substrate, an adhesive film, a heat reflective film, an adhesive film and a glass substrate in this order, cutting the adhesive films and the heat reflective film protruding from the edge of a pair of glass substrates to remove the protruded part, and heating and pressuring the whole to integrate.
The heat reflective film is a film obtained by alternately laminating an oxide layer and a metal layer on, for example, a polyester film produced by a drawing process. However, in a resin film produced by a drawing process, stress by drawing is present as residual stress. The residual stress causes thermal shrinkage by heating and pressurization in manufacturing a laminated glass, thereby generating wrinkles and the like in a heat reflective film containing the resin film.
As a means to suppress generation of wrinkles and the like in a heat reflective film, a means that thermal shrinkage of a resin film constituting a base material in a heat reflective film is set to a specific range is known (for example, see Patent Document 1).